Ever since it arrived in the 1990s as an IBM product, and later after 2005 as a Lenovo product, the premium-priced ThinkPad laptop has been known for its distinctive black color, rugged construction and, in particular, its terrific keyboard.

Now, in a new version of its thin and light X1 Carbon model, Lenovo is taking a risk with the classic ThinkPad keyboard. It’s killing the traditional row of function keys at the top and replacing it with a morphing strip of virtual keys. It’s also adding gesture control and voice control.

After a few days of testing this new ThinkPad, my conclusion is that while these efforts are admirable, they aren’t fully realized, or even, properly functional in some cases. On top of that, I found that the new X1 Carbon had weak battery life, despite its use of a new battery-boosting Intel processor and its high price, which starts at $1,299 and rises to more than $2,000.

The new X1 Carbon retains the key ThinkPad virtues. It’s still rugged, while weighing around three pounds. The 14-inch screen is sharp and vivid. The main part of the keyboard has been made even better, with a bigger touchpad, bigger Control key, and more prominent Delete, Home and End keys. The iconic ThinkPad TrackPoint red center-navigation button remains. The screen can lie flat, and you can rotate its contents so somebody sitting across from you can see them better.

Lenovo The new X1 Carbon in Lay Flat mode

But I found the new control features mixed, at best. While I love the idea of the morphing row of function icons, I don’t think Lenovo went far enough with it, so it wasn’t all that valuable to me. And I found the voice control almost useless. The gestures were better, but took a lot of practice and, at least for me, didn’t work consistently enough to be trusted.

The new top keyboard row, called the Adaptive Function Row, is a wide, thin touchscreen, on which different function-control icons appear, depending on what you’re doing with the computer.

For instance, if you’re in a Web browser, this row offers icons for going back a page or opening a new tab, among other functions. If you’re in a conferencing app, like Skype, it shows icons for muting the microphone or turning the camera on and off. In standard mode, the icons include ones for search, open apps, all apps and bringing up cloud storage.

Other functions formerly found on the physical function key row, like screen brightness and the old-fashioned parade of F keys, are also now on the touch strip, whose appearance can be manually cycled through four layouts by tapping an icon at its left edge. The physical “Fn” key, which typically toggles between functions and F-key shortcuts, is gone.

But I wanted more. For instance, in the Web browser iteration, there was no shortcut key for, say, creating a bookmark, or for going to your favorite search engine or social network. The adaptive strip that appears when you launch Microsoft Office is mainly just the original F keys — presumably for Excel Jedis who depend on keyboard shortcuts. But there’s no icon for common functions like Undo or spell-check or making text bold or underlined.

And one common function formerly found on the physical top row — the “play” controls for music and video — is missing altogether from the new virtual strip. It has been relegated to gesture and vocal commands.

Lenovo told me that it had limited space for icons, and limited flexibility for users’ choice in this first version.

Lenovo

Overall, I found the Adaptive Row less useful than I had hoped. But it was much more useful for me than the gestures and, especially, the voice-command feature, both of which can be triggered from the new function strip.

The voice controls, provided by Nuance, failed utterly for me unless I was wearing microphone-equipped earbuds, which aren’t supposed to be necessary. Again and again, even when uttering the example phrases in the help guide, it said “I’m not sure what to do with that.” I even took the time to do optional training, but to no avail. I wouldn’t buy this machine for the voice-control feature.

Gestures worked better in apps like PowerPoint and iTunes and the Windows video player, where you could use them to skip, go back, play and pause. But they felt clumsy to use, weren’t reliable, and I’d guess would take more practice than most folks would care to invest to get working smoothly.

Then there’s the battery. In my standard, tough battery test, where I disable all power-saving features, crank the brightness to 100 percent, keep the Wi-Fi on while collecting email and playing an endless loop of music, the new X1 Carbon lasted just about five hours. That’s only half of what the similar-weight MacBook Air got in the same test. In more normal use, the Lenovo would likely stretch to six hours.

There are several factors that help explain this, even though both machines use Intel’s battery-friendly fourth-generation Core processors. The Lenovo’s battery is smaller (though the machine weighs a bit more), and the model I tested has a touchscreen, which consumes power. The Mac does not.

Currently, the X1 Carbon is available in two configurations — a lower-end model for $1,499 and a higher-end edition for $2,099. There will soon be configurable models starting at $1,299. The one I tested was a pre-production version of a configurable model, which would cost $1,679 because it has extra memory and storage.

I actually tested two identical models, because the first one Lenovo sent me had a bug wherein the touchscreen sometimes stopped responding to touch after it had been in sleep mode. The second machine didn’t show any trace of this problem. Lenovo is investigating, and noted that it had just loaded new software onto my first test machine.

Bottom line: The idea of adaptive virtual keys is a good one, and gestures and voice commands make sense, too. In theory. But Lenovo did only from okay to awful in these three categories in this first effort.